This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. To examine the changes in LHRH release at menopause and premenopause.[unreadable] [unreadable] Despite the fact that menopause is a critical event in women's lives, the mechanism leading to menopause and problems [unreadable] associated with menopause are not well understood. First, we investigated whether LHRH release in female rhesus [unreadable] monkeys at menopause and during the transitional stage before menopause differs from eugonadal young females. The [unreadable] results indicate that LHRH release is pulsatile in both young and aged monkeys, mean concentrations of LHRH increase [unreadable] during reproductive aging, and LHRH pulse frequency does not change with aging. We concluded that not only do LHRH [unreadable] neurons have the continued capacity to release LHRH in a pulsatile manner, but its activity is enhanced in aged primates. [unreadable] Second, we investigated whether an aging-related reduction in growth hormone release is due to a decrease in growth [unreadable] hormone-releasing hormone or an increase in somatostatin with aging. Our results suggest that a decrease in growth [unreadable] hormone-releasing hormone and an increase in somatostatin occurs at the time of menopause. These findings are [unreadable] important for understanding diseases and health conditions in aged women. We will further continue this research in the [unreadable] future. This research used WNPRC Animal Services and Assay Services. Currently no funding, but we hope to continue this [unreadable] important work.